


A Throne’s Weight

by VerdantMoth



Category: Merlin (TV)
Genre: Anal Sex, Consensual Infidelity, M/M, Mpreg, Sex Rituals, Sort Of, Voyeurism
Language: English
Status: Completed
Published: 2018-08-05
Updated: 2018-09-20
Packaged: 2019-08-23 17:06:11
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 4,691
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16622933
Author URL: https://archiveofourown.org/users/VerdantMoth/pseuds/VerdantMoth
Summary: Hot, too hot, and alive around him, this body hums for him. Was made for him. He is almost afraid to move into the slick channel, overwhelmed by the lust that fills him. He reaches down and grips himself tightly, to prevent himself from coming too early.





	1. The Cost of an Heir

They bring in the next woman and Arthur is disappointed, as usual, by the thick robes hiding  _ any  _ view of her he might have. He knows this is the rule he has agreed to, knows this is the contract he has signed.

It would still be nice to get a glimpse of his nameless lover, of the woman who might carry his seed.

She is positioned on the table before him, but when they lift the robes when they move the cloth, he is afforded no glimpse of her back side, no offering of flesh. Only more blue silk, cut through with a single slit. He glances towards Guinevere who looks at him with ever-distant eyes.

“I am told it is what she wished, sire. The magic will guide you through.”  The last words make her visibly uncomfortable, and Arthur yearns to remind her this solutions was her own.

She offered him noblewomen and he bore no heir. She moved on to the peasants, the servants, and still his seed did not take. Guinevere had the idea that perhaps a man born from magic, needed magic to produce.

His eyes turn back to the body before him. The robes are thick, swirled about the neck, a heavy hood covering the face. It is still hot in Camelot and he worries about this person. The robes do not hide the surprisingly broad shoulders, nor can the conceal the narrow waist.

Arthur goes to place his hands on the small of his partners back, but Leon gently stops him. When Arthur looks at him inquisitively, Leon shrugs. “Per request, there is to be no contact that is not strictly necessary. The magic will guide you through.”

He repeats the Queen’s words a bit sorrowfully.

Arthur frowns, but there is nothing to be done. He unlaces his trousers, pulls himself out. He is soft, though it is of no surprise given his audience, given the bundle of cloth he is meant to bed. He closes his eyes as he licks his hand. He doesn’t have to dream anymore, to imagine. Simply a few well practiced tugs have him hard and dripping.

He steps closer, tries to figure out how he is to do this with blue silk impeding his way. As if in answer, a soft breeze sighs through the room, and the cloth opens to dark curls, already glistening. He sighs, pleased that his path will be easy this time

He is unsure how to maneuver, how to enter, when magic wraps around the base of him. Warm, fizzy,  _ familiar  _ though he has no clue why, it guides him into a hole like nothing he has ever felt before.

Hot, too hot, and alive around him, this body  _ hums  _ for him. Was made for him. He is almost afraid to move into the slick channel, overwhelmed by the lust that fills him. He reaches down and grips himself tightly, to prevent himself from coming too early.

“Something is different!” He gasp out. He does not know how to explain to them. Of all of the women he has had, none have ever felt like this. The magic gives him no chance to speak further, pulling at his hips, setting a pace that gives him little time to think.

All he can do is  _ exist  _ in the tight, hot heat. He loses track of time, of his heartbeat, of anything that is not the grip around him. When he releases, his cry echoing off the stone walls, there is the briefest moment of his balls brushing something… something  _ other _ . But he is spilling before his brain can process, eyes screwed shut as galaxies come to life behind them and he shoots more seed then he has ever before. More than he thought one man could hold in himself.

He comes to, in an empty room, alone. The only evidence that what he experienced was not a fever dream are the strange, ropey-white streaks left on the table where his lover was, where had expected a puddle of slick.

It occurs to him, that Merlin had not stood in the crowd, eyes alight with whatever issue he took with Arthur’s current predicament. It hurts, more than the constant selling of his seed.

—-

Merlin is absent for a few days. When he returns his walk is stiff, but his eyes glow. He won’t tell Arthur where he was and Guinevere does nothing to push the issue. Arthur lets the issue drop after a week, but only because they both begin to mention the next possible heir bearer.

“We don’t even know if the last one failed yet.”  Arthur can’t explain to them this feeling he has, that it  _ did  _ take. It frightens him though he cannot explain why.

“We aren’t saying you need to bed her now, but we should go ahead and find someone, just in case.”  Guinevere is brushing her hair out while Arthur studies the documents in front of him. Merlin lazily scratches at his belly, a move that distracts Arthur unnecessarily.

“Gwen dear, there’s no entry into the coffer's logs for the latest…” he hesitates on what to call his partner.

He misses the look Merlin and Guinevere share. “There isn’t one. It was a free offering.”

Arthur glances up with a deep frown. “I thought the deal was each possible carrier would receive some form of compensation. For their troubles.”

Merlin’s shoulders jerk up. “It was refused this time.”

Something unsettling curls in Arthur’s belly, something thick and sour. “Part of the offering is an insurance that should the seed take, they give the baby up along with any rights.”

Gwen comes over, wraps her arms around Arthur’s shoulders. “I have no doubt the baby will come home to you, should it take.”

Arthur isn't convinced, but she is slipping into her own chambers before he can find the right words.

\---

In the end, he wins. They bring no new woman to Camelot's walls. Two months pass, and Guinevere stops bring the issue up. There’s a lightness to her step and a shine to her eyes. When he ask, she just smiles, kisses his cheek. “Soon, our troubles will be over.”

As Guinevere grows more excited though, Merlin grows more distant. He is never present in the mornings and he grimaces, hand pressed to his lower back, in the evenings. When Arthur tries to discuss the sudden excitement surrounding his Queen, Merlin grows terse with him, storms out of the room.

He tries to ask Guinevere one evening, but when the light about her dims, he decides to let things lie.

As long as he is not being forced into passionless joinings, he figures the strange, shifting moods of the castle are not his problem.

\---

Merlin and Arthur are sitting in his chambers one evening, when Arthur notices something. He’s not sure what, at first. Merlin’s cheeks are hollow as ever, his shoulders broad but fragile. His hips are still narrow as he stands before the fire, but when he turns… When Arthur sees him from the side he sucks in a breath.

It is small, probably not noticeable on someone with any fat elsewhere, but there’s the faintest  rounding to Merlin’s lean belly. Arthur lets his eyes drift over the rest of Merlin, over his narrow wrist, over the sharp jaw. He can see no other fattening of Merlin, who turns to catch Arthur studying him. He gives Arthur a sharp look.

Arthur turns away, swallows thickly and thinks he does not want want to know what his brain is thinking.

\---

He watches Merlin more closely, though. Notices the way he picks at his food and the shadows that curl beneath his eyes. Notices the flashes of pain on his face, the way he has a servant knead at his back.

Mostly, he notices the ever growing belly that Merlin takes to hiding beneath thick shirts and heavy robes. The weather is beginning to cool, but not as quickly as Merlin’s winter clothes come out.  Guinevere takes to pulling Merlin away to hidden alcoves, where their whispers drift out the windows and away from Arthur’s ears.

He tries to corner the sorcerer, tries to get a moment alone with him, but Merlin is ever busy and never present. Arthur cannot catch the ghost of his old friend.

—-

Arthur enters Guinevere's chambers one evening, forgetting to knock. He is surprised to find Merlin asleep in a chair, feet propped up on the Queen’s bed. Guinevere is nowhere to be found.

Despite the raging fire, Merlin is swaddled in thick blankets Arthur is sure Guinevere procured for him. It is early in the evening, too early for Merlin to be sleeping so deeply. He is unsure what compels him, a feeling he always has when Merlin is involved, but he shuts the door behind him and enters the room.

Merlin’s snores softly, the only sound aside from the rustling of Arthur’s clothing as he approaches his servant-turned-court magician.

The closer he get the heavier his heart thuds, and then he is there in front of Merlin, ripping the blanket off.

He sucks in a breath that taste like the heat of burning wood at the sight that greets him. Merlin stands with an outraged cry, hands immediately protecting his belly.

Why Merlin was under the blankets shirtless is an issue Arthur will contemplate later. He is currently too busy being horrified by the grotesque skin stretching around the lower part of Merlin's torso.

Part of him wants to reach out, to touch the ugly purple marks where the skin looks to burst open. Part of him wants to run his fingers through the dark smattering of curls, and to ignore the strange roundness of Merlin’s belly.

“What are you doing in here, Arthur?”

His hand is still hovering, fingers ghosting over Merlin’s skin as he answers distractedly. “I was looking for Gwen. We needed to discuss…”  He cannot remember what.

He raises both hands, holds them an inch from Merlin. “What-.”  That is not the question he wants to ask. “Who did this to you?”

Merlin scoffs at him. “Really, Arthur?”

Arthur shakes his head. “It cannot be. This is impossible.”

Merlin grips the king’s wrist pulls until Arthur cannot ignore the firmness between his fingers.

“And yet.”

Arthur yanks his hands back as, hands burned by the ice of Merlin’s skin.

“You?”

Merlin nods. “A gift of my unusual birth, a blessing from an old Priestess.”

Arthur turns away from him, head spinning. “Oh Merlin. You should not have done this.”

Merlin reaches out, tries to place a hand on Arthur's shoulder, but the king knocks him away. “Arthur. Guinevere knows. She helped me find the ritual, set it up for me.”

Arthur shakes his head, feels as though he might be sick. “No, Merlin. You should not have done this. I do not want an heir, if it cost you this, if it cost  _ us  _ this.”

He goes to leave, has the door open and has almost escaped when he hears Merlin whisper, “You will have your heir, Arthur. Camelot will have her son. You can banish me after he is born.”

Arthur thinks he just might.


	2. Albion’s Son

**Summary for the Chapter:**

> Merlin won’t let anyone in the room when labor begins. Not even Gaius, despite advisement. Arthur hovers outside the heavy door, Gwen on his left and the physician on his right. They can hear nothing from the room, not a sound. Arthur knocked on the door at one point, worried that perhaps the sorcerer had cast some kind of illusion. That they were standing before stone walls.

Merlin won’t let anyone in the room when labor begins. Not even Gaius, despite advisement. Arthur hovers outside the heavy door, Gwen on his left and the physician on his right. They can hear nothing from the room, not a sound. Arthur knocked on the door at one point, worried that perhaps the sorcerer had cast some kind of illusion. That they were standing before stone walls.

Gaius yawns, Gwen shifts, sinks down and slumps against an old tapestry. Arthur, for his part, can’t keep still. He’s got one hand on the hilt of his sword, and the other keeps finding its way into his mouth. His knuckles are raw at this point. He’s about to raise a fist to the door once more, to pound on the wood and  _ demand  _ Merlin open the door for him, when the door opens up right as he makes contact with the wood. No one moves for several moments. Arthur drops his fist and is about to storm into the dark room when Gwen places a hand on his shoulder. “I think I’m supposed to go in there.”

Arthur turns to her with outrage. “That is  _ my  _ sorcerer and  _ my  _ son in there!”

Gwen turns him to him, with a fire in her eyes. “  _ Our  _ son. And can’t you feel it? I’m meant to go in there. You’re not to come with.”

Arthur doesn’t. He can’t feel anything, He stares into the murky darkness of the room, feels the heat. There’s still no sound, no sign of life in there. He reaches a hand out but an unpleasant feeling curls around the base of his spine. Everything in him feels slick, ill, twisted.

“I think perhaps she is right, Your Majesty.” Gaius places a heavy hand on his shoulder.

Arthur bites on his knuckles, taste copper. He nods though and steps to the side. Gwen has has barely cleared the door when it slams shut. Arthur immediately throws himself at the door, pounds his fist into the wood until his hands are bloody and he thinks he’s broken a finger. Gaius pulls him away, tries to usher him towards his home but Arthur will not leave.

“My wife, my son, and my…,” he takes a breath, “and Merlin are locked in a room I cannot enter. I will not leave.”

Gaius does not try to persuade him otherwise. He instead pulls out a few rags and some salve and takes to bandaging Arthur’s hands. Night has settled in and the stars are gleaming bright. Arthur studies them, notes how they seem to shift a little.

“Unusual, Your Majesty, the way the stars are tonight. Ever bright but I can see no usual constellation. A child born under such inconsistency can have no predictable path.”

“You mean to say my son’s life will be difficult?”

“I mean to say this child will change the world. In every conceivable way.”

Arthur is about to respond, to challenge his old friend, when the door creaks open once more. Light glimmers, warm and orange, and Gwen appears. She glows, but Arthur has no eyes for her. In her arms is the smallest child Arthur has ever seen. His skin is pale, so pale. “He looks like he has ice in his veins.”

Gwen coos at the child, runs her hand across cheeks that are already pronounced, traces the shell of his ears. Arthur thinks he is bald until he strokes a finger across the babe’s crown. “It should darken, along with his skin, as he grows. Though I fear the poor boy has inherited your fair coloring.”

“No,” Arthur answers. “No perhaps that is the best. No one can deny his parentage.”  He strokes his son’s cheeks, feels the smoothness of the skin. “And his eyes? Are they blue?”

Gwen doesn’t answer. She turns away from him, cradles his son and rocks him. She hums a lullaby that Arthur has hear in the lower town before.

“Gwen. What color are his eyes?”

“Merlin says they should settle by the next moon.”

“Guinevere. What does that mean!”

The baby begins to wail, loud and boisterous despite his size. Gwen turns to him with wild eyes. “You will contain yourself, Arthur! You will hold your temper.”  She bounces his son in his arms, coos at him until the child calms himself.

Arthur takes a step back, takes several breaths. “Please, Guinevere.”

“They’re-” Gwen bites her lip, “Arthur, they change. They shift between molten gold and icy blue and dim silver. Merlin swears they’ll settle though.”

Arthur turns away from her then, and thinks he might be ready to leave when Gwen places a hand on his shoulder. She offers him the boy and he takes him in his arms. He’s so small Arthur is afraid to breath lest he disturb the small creature. “I believe he is ready to speak to you, Arthur. And to name the boy.”

Arthur whips his head up but Gwen shakes her head. “It is the least we can do, to honor his sacrifice, Arthur.”

Arthur nods. He goes to offer his son back to her, but she shakes her head. Her warm brown eyes, soft as they are, cool for a moment before she is turning away. She loops her arm in Gaius. “Come, let’s get some rest shall we?”

Arthur enters the room and is immediately accosted by the stifling heat, the stench of it. Merlin is curled on his side and Arthur can see dark circles on the sheets below his pelvic. Merlin’s color is somehow paler than their son’s, his face more wane. “Do you love Mordred, Arthur?” His voice is soft and shattered.

Arthur regards Mordred. He’s asleep, nuzzling his face into Arthur’s shirt. Arthur fears him, and all he might become. He worries for him; that people might discover the strange truth of his birth, that his power might grow to consume him. That he will have no place in this world, with no path laying before him.

But he does love this strange creature. He would do anything for him.

“Would you denounce your kingdom, if it came to it?”

Arthur says, “Of course,” before he can even process the question.

Merlin smiles at him. “Then you must protect him, Arthur. At all cost. You must promise me, here and now, that you would slay your own wife to protect that child. He is your future. He is  _ Albion’s  _ future.”

“Merlin, you’re talking crazy. You need rest.”

Merlin grips Arthur’s wrist in a clammy hold. “Arthur you must! Everything you have ever strived for, everything I have worked for rest on this child’s head. You must swear to me you will see that he succeeds. You and Gwen hold Albion in your hands. Everything you have trained for, everything she has sacrificed, the plans she and I and you muddled through, will all be for nothing if you are not prepared to do this!”

“And where will you be in all of this, Merlin?”

Merlin smiles at him. It’s a gruesome stretching of the lips that causes Arthur to cradle Mordred closer to him. “You’re to banish me, Arthur. Wasn’t that the deal?”

“Merlin!” Arthur’s outraged gasp causes Mordred to shift, but the babe doesn’t stir. “You know I was just angry. I would never do that. Not to you.”

Merlin waves a hand and the sheets beneath him are replaced with fresh ones. The room cools and a breeze flows through. “Lie with me a moment, Arthur. Place our son between us.”

Arthur does as he is asked, carefully settling himself beside Merlin, positioning Mordred in the small space between their chest. “Merlin, what is going on?”

“Do you love Gwen?”

“Yes.”

“And are you happy with her? Are you satisfied?”

“I’m content.”

Merlin reaches out and strokes a finger across Arthur’s lips. “Do you love me, Arthur? Are you happy with me?”

Arthur doesn’t hesitate. “With every fiber of my being.”

Merlin closes his eyes. “I was afraid of that answer. I’m afraid you will have to forgive me, then Arthur.” He leans over and kisses Arthur firmly. Something warm, salty,  _ wet  _ drips between their lips.

“Merlin, please. What is going on?”

“Be happy, Arthur. Be happy with Gwen, and with Mordred, and with your knights. Forget me. Live your life. Your best life.” Merlin swallows and it’s loud in the room. “I’ve already arranged for a wet nurse. Gwen knows who she is, how to compensate her. Gwen will stay in her chambers with Mordred, until his eyes have adjusted. Gaius should be able to train the boy in the old ways, but should something happen he has instructions for an old friend of mine.”

Long fingers stroke Arthur’s brows, his nose. Merlin wipes a thumb under his eyes. “I’d like to settle in Ealdor, if possible. There is an old willow, where Will and I use to hide.”  He closes his eyes. It gets to quiet in the room and Arthur raises himself up on an elbow.

“Merlin?” He picks Mordred up and holds him in one arm as he shakes Merlin. Merlin manages to open his eyes for a moment and he places a hand on Mordred's head. His eyes drift shut for a long time, before he speaks again.

“Thank you, Arthur, for being my friend. I can’t wait to see you again.”


	3. The Price of Destiny

Mordred is a quiet child. Merlin was right, his eyes eventually settled, but it took six months, and Arthur still isn’t quite sure they’re completely right. They’re a dark blue, so dark that most people think them grey. But Arthur can see the silver brimming beneath the surface. Gaius says he has seen no magic take that color before, and Arthur knows it is because Mordred is perhaps the most unlikely creature on this earth. The only one of his kind.

Arthur thinks it might be lonely for Mordred. That perhaps that is why he sits so still, remains so quiet. As a child Arthur can only recall three times the boy ever cried. The night when Merlin left them, the morning he managed to levitate himself out of his cradle, only to land on the floor, and the afternoon Gwen revealed the truth about his birth to him.

They’ve tried, as parents, to give him a life free from the burdens of reign; to allow him a childhood unlike either of their own. But Mordred separates himself from his peers, preferring to spend his time lost in the forest befriending the wild or bent over his books learning a language no one else speaks. Try as he might, Arthur cannot connect to his son. Sometimes he hates Merlin for this, sometimes he despises Gwen for their predicament. Yet even as Mordred grows into his shoulders, into his sharp ears, Arthur cannot bring himself to regret any of it.

Mostly, he watches his son in the gardens, raising flowers and demolishing small hills. He doesn’t press the boy for words, simply relishes the quiet time spent walking the borders of Camelot. Arthur’s unused to the silent treks.

“Are we going to Willow, Father?” Arthur is startled, jerks upright and nearly sending him off his horse.

He turns towards Mordred, regards the boy even as his son watches the sky. Reading things in the cloud that may or may not be there.

“I’m not sure we’ll have the time, this trip. Mother will be expecting us back soon.” Arthur is quiet in his response, hesitant. The wind picks up, a chill in the air that has to less to do with a shift in seasons that Arthur would like.

“Mother knows. It was Mother’s suggestion.”  Mordred still doesn’t look at him, but there is a weariness, a comradery in his voice that makes Arthur suppress a smile.

“Then I suppose a small detour cannot hurt.” He clicks his tongue, pulls the reins of his horse. They’re only an hours ride from the Willow anyway.

```

The Willow is spectacular, and entirely out of place. Pale leaves whose pink only show in the right light, and too large for half-century age. The villagers say it sprung up overnight, full-grown and strange colored, and never changed. Arthur isn’t sure he believes them, but he has no proof otherwise. Mordred doesn’t seem to care where the tree came from.

As soon as it’s in view he spurs his horse into a gallop, leaving his father in the dust. Arthur doesn’t hurry to catch up. He rather enjoys the wild grin on Mordred’s face, the whoop and laughter that trail behind him. His son looks so alive in the moment Arthur wishes there was a way to capture the image, to keep it framed beside his bed.

He only hurries his stead when he can no longer see the dark mop of hair.

He doesn’t worry about hitching his horse. They never seem to spook or flee beneath the willow, content to graze and wander beneath the branches. Arthur can hear Mordred’s rapid conversation, can feel the air buz with his excitement. It makes his heart clench, and as always he’s a little afraid to step around the trunk, to see what awaits him. He sucks in a breath, closes his eyes, and lets the wind push him forward.

Mordred's back is to him.  Tiny blue dragons and firey butterflies dance around him, and though Arthur cannot see his face he knows his eyes are that strange and liquid silver. When the creatures fade away Arthur can see Merlin. He’s got the same concern carved beneath his eyes he has when he watches his son’s eyes, but his smile is true and bright.

“Gaius has taught you well, has he?” Arthur thinks he is imagining the soft disappointment in Merlin’s voice.

Mordred answers him sharply. “Don’t be daft. The notes in your books taught me this. Gaius is old and foolish and too tired to teach me.”

Merlin gives him a look. Arthur knows they’re having a quiet conversation. One of those that makes Gwen bitter with jealousy but secretly relieves Arthur. What he does not know, means that he does not have to pick a side.

“He is old and tired, though.” Mordred’s sullen in his answer.

Merlin rolls his eyes. “You still owe him your respect. He has much to teach you.”

“Fine.” Mordred grows bored with the conversation and stretches up. “Got any snacks?” He’s already sauntering off toward the cottage Merlin keeps.

Arthur takes this as his chance to move in. He hesitates before Merlin, but does not flinch when Merlin’s hand finds his jaw, when Merlin’s tongue finds his lips. “Mordred has certainly inherited your appetite, Arthur,” he whispers.

Arthur snorts. “Please, you’d have eaten us out of the castle, had I allowed it.”

Merlin doesn’t bother to refute the lie. He leans in, kisses Arthur long and hard, until spots begin to form behind his eyes. Arthur has to gently push him away.

“Merlin, some of us need air.” His voice’s raspiness makes him flush, where the kissing hadn’t.

It’s the wrong thing to say. Arthur can see it in the way Merlin’s features harden, the way he traces the soft lines around Arthur’s eyes. Merlin’s face is as smooth as the day he left, the rest of him soft and boyish still. Merlin turns towards the cottage, he studies Mordred as the young man lounges in the grass munching on Merlin’s cheese.

“How is Guinevere?” Merlin asks absently.

“She’s good. Happy.” Arthur says just as absently.

“And Lance? The boys?”

Arthur smiles. “Proud as ever and probably grateful for a month without the king and the prince.” 

Merlin sags against him, weary with age old arguments.

“I know, I know. Do not speak that way.” Arthur kisses his temple. “She misses you, you know. Wishes you would come visit.”

“She only thinks that’s what she wants. Because she is so good and so noble she cannot imagine her own jealousy or hatred. But it’s for the best, Arthur, that I stay here.” Merlin’s voice is flat.

“Come. Let’s not argue. Mordred and I only have so long before we must return to the castle.” Arthur says quietly. He grabs Merlin’s hand in his own, notes the softness of the skin against his own rough hand. He doesn’t know how long they have, and he hates the grey creeping along his own temple, but he’s told Merlin before, “It doesn’t do to dwell on dreams and wishes. Reality is here and meant to be held in our hands, caressed.”

He intends to do just that, once Mordred is done tugging Merlin to a stream dripping from his fingers. The future, despite Merlin and Mordred's certainty, is never truly known, and as he glances up at the fading sun, sees the first star appear out of place, he taps an old wound that hasn't ached in many months, and doesn't fear tomorrow.

 


End file.
